It’s unlikely you were there in 1915 for the Panama-California Exposition in San Diego’s Balboa Park.

But a new web-based project recently launched by Balboa Park Central, the Balboa Park Online Collaborative and a group of Balboa Park museums, gives you a sense of what it was like and how that compares to what the park looks like now.

Park institutions are partnering with Historypin, a web tool that allows users to “pin” photos, videos and audio clips onto a Google Map showing the park. The tool has a “street view” capability (although not available on all photos) that allows viewers to juxtapose the then and now images.

The Online Collaborative has “seeded” the site with more than 100 images from park organizations, including the park support group, the Committee of One Hundred, but hopes the public will contribute its own images — not just of the 1915 Exposition, but of things they have done in Balboa Park through the years (the website already has several weddings on it).

The Historypin-enhanced website is expected to be operational through the 2015 Centennial Celebration of the Panama-California Exposition.